1. Field of the Invention
The present invention relates to a system and method for automatically controlling temperature in a vehicle.
2. Background Art
Current automatic temperature control (ATC) units may operate more often than required to maintain the vehicle cabin temperature at a desired level, which may result in reduced fuel economy. These ATC units oscillate back and forth around a desired temperature or temperature range with the controller operating continuously to either cool or heat the vehicle cabin in an attempt to maintain the desired temperature.
A system and method for controlling temperature within a vehicle cabin include monitoring various temperature sensors to determine current operating conditions, determining a desired temperature or temperature range based on occupant input, dynamically estimating a temperature gradient based on changes in the current operating conditions over a predetermined time, predicting a time when the desired temperature or temperature range will be attained based on the gradient and the current operating conditions, and controlling a heating/cooling system based on the predicted time. Controlling the heating/cooling system may include shutting off the system at the predicted time, or turning on the system at the predicted time. The process of prediction may include linear, non-linear, or empirical methods.
The present invention includes a number of advantages. For example, the present invention uses a predictive controller that estimates when a desired temperature setting will be reached given current conditions and current momentum of the system. This information is used to shut down the heating/cooling system so that it does not run continuously and, therefore, may result in improved fuel economy. In addition, the present invention may be used to optimize current linear heating/cooling controllers.